Sendero Resources Corp. (TSXV: SEND) has released results of advanced 3D magnetic modelling at its 100%-owned Peñas Negras copper-gold project in La Rioja, Argentina, identifying multiple porphyry and epithermal-style targets with roots extending to approximately three kilometres depth. The company states the model reveals several discrete, kilometre-scale magnetic bodies interpreted as oxidised intrusions characteristic of porphyry Cu-Au(-Mo) systems, as well as a preserved lithocap across much of the project. The disclosure suggests the project may host a cluster of mineralised systems rather than a single target, a distinction that investors in Argentine copper-gold exploration may find relevant.

Key Points

  • Sendero Resources Corp. (TSXV: SEND / FSE: 9O40) operates the Peñas Negras copper-gold project in the Vicuña Belt, La Rioja, Argentina
  • 3D inversion of airborne magnetic survey data has modelled subsurface geology to approximately 3 km depth, identifying porphyry and epithermal targets
  • Four magnetic classes defined: lithocap, magnetite-destructive alteration, andesitic host rock, and interpreted diorite intrusions
  • Investors may watch for drilling updates at untested deep targets, including the strongly magnetic body beneath Cerro Verde Sur

What the 3D Magnetic Model Reveals at Peñas Negras

The 3D inversion and classification of aeromagnetic data produced a geological model extending to approximately three kilometres depth. Four statistically separated magnetic classes were identified: a thin, flat-lying lithocap layer; thick horizontal zones of magnetite-destructive alteration with near-vertical chimneys interpreted as hydrothermal root zones; andesitic volcanic host rock comprising most of the model volume; and steep, pipe-like diorite intrusions with susceptibility values ranging from 7.05 to 84.7 ×10⁻³ SI. The release states that stacked lithocap layers at one section approximately nine kilometres north of La Ollita are consistent with more than one overlapping hydrothermal event, a geometry referred to as telescoping.

Magnetic Coverage Over Glacial and Alluvial Overburden

The company notes that most of Peñas Negras is concealed beneath glacial and alluvial sediments, making surface mapping insufficient for full geological characterisation. The release explains that magnetic response is largely controlled by magnetite, which hydrothermal fluids can either create or destroy, allowing the survey to map alteration patterns as well as rock types at depth. The announcement states that the 3D magnetic inversion is the only method applied at the project capable of imaging subsurface geology to kilometre-scale depth across the entire concession area of 211.77 km².

Key Target Areas and Historical Drilling Context

At La Ollita, historical shallow drilling sits above a root zone of magnetite-destructive alteration that extends to depth, and the deeper portion of the system remains untested. At Cerro Verde Sur, three shallow holes drilled in 2026 intersected anomalous gold in the lithocap but did not reach the strongly magnetic body below, which the company states remains untested. At Cerro Verde Norte, drilling by Anglo American between 2011 and 2012 intersected lithocap hydrothermal breccia near surface and granitic intrusive rocks at depth, consistent with model predictions, though whether the granite represents a mineralising intrusion or older basement has not been determined.